Thursday, 20:55...
They had been trudging through the squelchy mud near the edge of the lake for nearly twenty minutes. Remus, who had eyed the waxing sickle moon the whole while, suppressed a shiver as he heard the owl call in the distance and the thin rustle of wind through the drying leaves overhead. Something mysterious pumped through his blood, singing a call as old as time, and he felt his heart quicken at the thought of the impending full moon and the transformation that would follow.
"I'm not entirely sure there are kelpies in the lake at all," he said softly, trudging behind McKinnon, who had her wand out and was prodding a lily pad. "Maybe if we –"
"Quiet," she barked, imperious and Slytherin. She bent down, her wand skimming the surface of the black water.
Remus cleared his throat, inhaling the chill air. "The list says kelpie fur," he said, for what seemed to be the tenth time. "I say we check Professor Slughorn's office, that cupboard where he keeps his potions stores. There's bound to be some kelpie hair in there. Anyway, even if we do manage to coax a kelpie up out of the water, what exactly will we use to subdue it?" He thought of his Defence Against the Dark Arts text and shuddered. "They fight."
"You watch," instructed McKinnon. She sighed, glancing over at her partner. He stood grey and meagre in the sombre moonlight, looking distinctly uncomfortable, his boots sinking in mud. Remus Lupin, she wondered to herself. How did I get stuck with him?
Something green-gray and scaly hit the water then, making small ripples that floated to the bank, disturbing the long grass. A frog hopped beneath the lake's surface and Remus stiffened. Marlene bent ever lower, her wand out and her eyes wide, anticipating the sight of the kelpie.
Sure enough, it rose then, bubbling the dark water and splashing lightly against the assembled lily pads and cattails. For a moment Remus hovered, perplexed and excited, ready for a nice bath when the kelpie's hair had been surrendered, but the next moment he blinked. Next to him, Marlene let out a shrill cry.
The thing rising from the deep was no kelpie. For the briefest of moments, Remus thought of mermen. Surely, the creature had their long, tangled hair and murky skin. However, it quickly ascended in the form of human, darker and more frightening than any merperson. Its beard seemed to stretch on for eternity, a dark cloak of grey entwined with algae. His hands, Remus noted almost clinically through his panic, were connected with translucent webbing, but his eyes were pure scarlet, flashing like rubies.
"I – I –," he stammered hopelessly, flailing backwards as the creature – part man with a shining tail, yet more hideous than any fish – dragged itself through the mire. Its teeth were sharp and pointed and its webbed fingers reached out a cool, slimy touch on Remus' neck.
"Get back," hollered Marlene. Without warning she shoved him so hard that Remus lost his balance and landed on his bum in the damp grass. "Protego!" she shouted, casting an invisible shield between herself, Remus and the bedraggled, drowned-looking man who was slowly making his way nearer. The shield burst like a bubble at his touch. "Glisseo!"
The sucking mud swirled beneath the creature's body, forming a slippery slide that threatened to cast him back into the deep. Inexplicably, the creature moved ever nearer, its fingers grasping for purchase and terrible squeaking sounds emerging where its awful tail slid forward.
"Oh, Merlin," breathed Marlene. She cast her eyes on Remus. "Lupin! Do something."
"T – Transmogrify," said Lupin, holding out his wand in one shaking hand. It was the only curse that came to mind, and he remembered – wildly, out of breath – Sirius using it on a stray cat on Hogsmeade. Not certain what the effects would be, he clenched his wand harder, trying to stop the inane drumming of his heart.
The man-creature cast a baleful red eye on Remus, but his fingers slipped from Remus' throat, then fisted Remus' jumper and at last retreated a pace. For a moment, he opened his maw, emitting a rotten, stinking odour; the next second he had turned himself into a shining silver fish and was gone, having thrown himself back into the lake.
Remus tried to rise and dropped heavily back down on the bank. He scooted away from the water which licked his boots, his heart thumping and his breathing shallow. "What was that?"
"Vodyanoy," Marlene stated with certainty. She gave Remus a grateful look, flooded with thanks. "Nice work. I thought we were done for." Remus nodded in urgent agreement, but she continued. "None of my spells worked. I should have remembered, it's almost impossible to make contact, given all the muck on their bodies. Lucky thing yours worked."
"Yeah, lucky. Here." He managed to get to his feet and helped Marlene up. "Potions stores?"
"Potions stores," she agreed heartily.
They turned to go, but Remus, whose senses were acute, paused, believing he had heard a sound. A shiver went through him. The noise was silky, eerie -- utterly horrifying. Remus felt a cold finger of fright trace down his back and he exchanged a glance with McKinnon, who was wide-eyed. Slowly, wands out, they turned around.
It was not the vodyanoy back for another attempt at strangulation, Remus noticed with surprise. It as only a horse. Small and forlorn it stood at the water's edge looking at them with soulful eyes. Relief flooded Remus and he slumped against his companion's shoulder a moment. The little pony neighed ever so slightly, a hopeful call in the dismal dark, and Remus found himself stepping closer despite McKinnon's sharp fingers biting into his arm.
Under his palm, the horse's silver-grey skin was icy cold and permeated with damp. Briny water dripped from its black mane and it shivered, stamping a nervous hoof into the mud. Inexplicably, Remus felt a desire to climb aboard the horse's back. He had never been particularly interested in horseback riding before, but the urge was overwhelming. He pressed a hand to the frigid flank of the beast and was just about to swing a leg over it when Marlene pulled him back.
"Are you mad? That's a kelpie!" she hissed. "Seco," she called out, wand at the ready, and a piece of drenched and dripping mane was instantly severed from the horse's body. "Accio," she hissed, summoning it to her as she shoved Remus. "Let's go."
Remus blanched. The dutiful, pathetic pony had transformed before their eyes. It gave off an imperious stare and snorted, throwing plumes of breath from its nostrils, which turned to fog in the cold air. Slowly, it took a step forward, shaking the ground beneath it. The thing seemed hardly to move but Remus suddenly realised he was nearly cut off; the horse had almost blocked the path back to the castle and Remus stood between it and the water.
Abandoning all pretense as the horse suddenly charged, Remus grappled with his wand. He found himself abruptly standing in knee-deep water; the disturbed lake splashed all around him as the kelpie nudged him further out, into deeper water. "Levicorpus," he shouted into the silence, his wand at his own temple. The kelpie bucked, neighed and moved again at him, but Remus was suspended in mid-air, out of the icy lake and barely beyond the horse's reach.
"Accio Lupin," shouted Marlene as the horse reared onto its back legs, bucking in an attempt to snare him. She staggered away from the reeds and the violent kelpie. When Remus descended at her side, she gave him an incredulous look. "Run!"